Draft-rigging.



E. H. SCHMIDT` DRAFT rflGGlNG= wPLfcMxoN YILED APR.24,9I1.

Patented Mau'. 21, 1916l 3 SHEETS-SHED 2" INVENTOR www Ess s .3W .Meu mm qw.. w 0%@ Hm :A H. SCHMIDT,

DRAM' RGGNG.

APPLwATmN FILED APR.24,191|.

lutcntw Mau: o1, 1916,

3 SHEETS SHEE 3.

WTNESSES mt, u @tu asliding bearing with the portion 2 of the casing, and the inner plate of each sethas a bearing on the inner walls of the pockets 16.

Each of the follower members is provided with an elongated slot 2G to receivel'a pin or rivet 21, which is inserted therethrough after the parts have been assembled, for the purpose of retaining them within Ithe casing. The elongation of the slot is suiicient to permit the followers to have the necessary longitudinal bufling and draft movements.

'When the friction plates'are inserted in the pockets and recesses of the friction plate shoes, the square shoulders a thereof at each side of the-projection 19 bear against the corresponding shoulders or surfaces 17'a adjacent to the recess 17 of the riction'plate shoes, thus giving them full bearing across nearly their entire width, and which is effestive in pushing the plates when in frictional contact with each other.

The operation will be readily understood. 1When a pulling force is applied by the coupler to the yoke, the rear follower is drawn forwardly, the front follower being held irnmovable by its engagement with the stops 5.

This pressure put upon the rear follower and resisted by the springs 14, causes la spreading action upon the friction plate shoes, which is transmitted through these shoes 'of the intercalated friction plates. The friction plates are thereby caused to Slide upon each other under pressure, each one of them exerting a friction resistance in proportion to the pressure Ywedging faces of the shoes and followers ln boiling, the operation is substantially the saine except that the rear follower is held tlxedly against the stops 4, while the front follower is forced rearwardly by the coupler shank. 1inthe forni shown, each follower, ,together with the pairs of friction plate shoes are arranged to enter the casing by an amount equal to onehalf of the total travel of the rigging, since the casing is open at both ends. lt will be obvious, however; that of the follower members mightconsti.- tute a closed end of the casing, in which case the movable follower will take up the entire movement, the immovable follower .simply providing pressure faces for engagement with the friction plate shoes with which it is in Contact.

In the modification of my invention shown in Figs. 8 to 12, the 'case or barrel 22, instead of being rectangular, as in the form first descrilxed,b is of cylindrical form. rEhe friction plate shoes 23 are also of curved segmental forni, and the friction plates or elements 24 are correspondingly curved to conform to the inner contour of the barrel.

ave also shown the friction plates as having 'lshaped projections 253, which are arapplied on the.

ranged to seat in correspondingly shaped slots 26 of the friction shoe plates. In this form also the outer friction plate ofeach vgroup is of a slightly different form from the others, in that its end portion 27 is bent inwardly to engage a slot 28 in the friction shoe plate, as shown in Fig. 8. In this forro I have shown four sets of the friction elements, but it will be understood that a greater orA less number of sets may be eniployed, as may be desired.

The modification illustrated in Fig. 13 is similar t0 that lastdescribed, except that l provide the followers, one of which is shown at 29, with a rounded projection 30, for engagement with the friction shoe plates, instead of an angular beveled projection. The engaging faces of the shoe plates .are corre-- spondin ly shaped, as shown at 31.

I pre erably provide means VIAwln ,reby the wedge engagement of the followers and the friction plate shoes will always be prevent-y ed from sticking, any tendency to which might keep the draft rigging from releasing properly after the removal of the compres sive force. By reference to Figs. l, 8 and 11, it will be noted that the portions of the friction shoes which form seats for the springs 14,.;slope toward the cent-er and have their highest points at The pressure of the releasing springs upon these inwardly.. sloping edges causes the friction shoes to be tipped or tilted, thereby releasing-their pon tions y from pressing engagement with the iniercalated friction plates, and releasing their contacting surfaces from wedging ein gagement with the followers 6 and 7, so that stickingis prevented. The same action will .occur with the construction shown in Fig. 13,

I By reference to Fig. l, it will be Yseen that by making the inner ends of the friction shoes tapering as shown, vthe tilting action of the springs may be further assisted by the fact that the shoes can tilt or rock about the corners a of each of the followers 6 and 7, the apex of the edge of each of the fol lowers being made blunt for this purpose. ln practice, this construction and arrangement brings about a sure and easy release of the wedging surfaces, overcoming any tendency they may have to stick or to grind into each other.

By reason of the manner in which the friction plates or elements are connected 0r engaged with the shoe plates,`1 avoid the necessity for any connecting pin or rivet, and also the necessity for spacers or distance pieces.` This greatly increases the ease of assembling, and is also an improvement in the operation. since` each friction plate is free to move inwardly oroutwardlv within its slot to automatically adjust itselfto wear which may take place between the plates, without the necessity of bending them, as would be the caseif their ends were forced irregularities as may occur.

to remain in a fixed position. The fact that the friction plates are entirely be easily removed, affords an opportunlty of putting in any number or combination of plates that may be necessary. Thus, if. it is necessary to double or treble the friction capacity of the rigging, this can be done by decreasing the'thickness of the plates and doubling or trebling their number.' In this manner the capacity can be increased to almost any practicable extent.

An important advantage of a frictional device of this character lies in the fact that a very large friction resistance can be secured with but a relatively small frictional or friction-producing pressure. IVith but a single pair of plates rubbing against each other, if it is desired to produce a certain friction'al resistance, it is necessary to generatebetween the rubbing surfaces a pressure transverse. to the line of movement f several times the desired frictional resistance. If the number of plates is doubled,

only about one-half this friction generating l to produce the pressure will be necessary and this holds same frictional resistance; true with any further increase in thenumber of inter-engaging surfaces. Therefore, any desirable unit pressure, or pressure in pounds per square inch, can be provided which will bring the working pressure so low that the rubbing of the surfaces of the friction elements will not cause excessive 'wear or abrasion.

By engaging the friction plates with the shoes in the manner described, an easy method of taking up wear since a thin plate of any desired thickness can be inserted to act as a shim to take up any wear that has taken place, after which the draft rigging will be in the same condition as when first putin service. The friction plates can be easily stamped from steel plates having smooth, flat surfaces, which will not change their condition throughout the life of the gear, as is the case where castings having rough surfaces are employed.

A draft rigging constructed in the manner herein described, admits of great variation in the various castings employed in the construction, since the plates, by reason of theirvloose engagement with the shoe members, will readily adjust themselves to such By placing the loose and c an is also provided,`

draft springs under initial compression, sufficient to cause the shoes to be forced constantly outwardly by reason of their enga gement with the followers, the plates may always be held in tight contact with each other, and with the shoes and Walls of the casing, even though there may be considerable variation in the sizes of the castings.

I do not desire to limit myself in the broader claims to the use of wedge means, such as described for actuating the friction members, since it is obvious that these may be actuated in various other ways.

1. In a friction draft rigging, 'a pair of oppositely facing wedges., shoes and springs interposed between said wedges, and a series of intercalated friction elements actuated bysaid shoes, substantially as described.

2. In a friction draft rigging, friction plates, a friction plate carrier having an inclined or sloping spring seat, and a spring adapted to bear against. said spring seat and thereby to rock said carrier for releasing the friction plates.

3. I n frictional shock absorbing mechanism,.a spring, a wedge, shoes interposed between the wedge and spring and actuated longitudinally and laterally by the wedge, substantially all of the pressure being transmitted directly through the wedge to said shoes, sets of friction elements carried longitudinally and pressed laterally by each of said shoes, and additional sets of friction elements interposed between the elements of the first named sets, said additional sets of friction elements beingvmovablev in a direc- 4tion opposite to said first named sets.

4. Ina friction draft rigging, a draft member, front and rear wedge members arranged to be actuated in reverse directions by the draft member, a plurality of friction plates, carriers having wedge surfaces engaging said wedges, and a plurality of intercalated friction plates mounted in said carriers, together with a spring interposed between the opposing carriers, substantially as described. r

In testimony whereof, I have hereunto set 

